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Installation

The Zfone beta is free to users, but is
not open source, so it can't be
packaged with official Linux (Ubuntu, Debian, OpenSUSE) distribution
repositories. Ready-to-install binaries are available for Windows and Mac OS
X.

Linux users must download the program, install the dependencies,
and build the program from a source tarball. The following sections describe how
to do this.

Downloading Zfone

First you have to register with the Zfone
Project, including accepting a Terms of Service agreement, and then you'll get
an email message with the information required to download a copy.

Installing the Dependencies

The dependencies are available via Debian or Ubuntu
repositories. The following instructions are written primarily for Debian,
although they've been tested on Ubuntu as well. For Ubuntu, where you see the
# root prompt, do
$ sudo from the
userspace prompt instead.

GNU nano
is my favorite command-line text editor, but of course you can use your
preferred text editor. If it's a GUI editor and you're opening a file that
requires root access, open it as root. For example:

$ sudo gedit filename

Remember that if you have opened a file with a text editor,
# indicates a comment line.

To install the dependencies, use the following command:

# aptitude install g++ automake autoconf iptables-dev libglib2.0-dev

Of course, you can use whichever GUI installer you have to install these programs.
If the installer says one of the programs is installed, don't worry about
it.

Loading the Kernel Modules

These modules come from the
iptables-dev
application you just installed.

Open /etc/modules:

# nano /etc/modules

Add these lines to the bottom of
the file:

# added for zfone
iptable_filter
ip_queue

Save and exit.

Building the Zfone Source

Make a zfone directory
wherever convenient; then download the
zfone-linux.tar file
from the site into the
zfone directory:

cd [path-to]/zfone
$ tar xvf zfone-linux.tar
# ./install.sh

Zfone automatically adds a file to run the
zfoned daemon script, which will run Zfone in the background until a voice or
videoconferencing application starts (see the next section for details). The
obvious thing to do is to run
update-modules to
incorporate it into the regular run-level startup sequences in rc.d*. However,
when I tested this,
update-modules worked
properly, but the daemon didn't start.

You'll want to run Zfone on startup so that you can simply start
your VoIP application. If the other end isn't running Zfone, however, you can
still have an unsecured conversation without concern about Zfone interfering
with the communication; the default setting is for Zfone to start encryption and
shut off if the called party doesn't support it.

Starting Zfone Automatically During Boot

The following instructions are for either the KDE or Gnome
window manager, until you get to the specific sections for KDE and Gnome.

To start Zfone automatically with Gizmo, create a new
script:

# nano /etc/init.d/zfonestart.sh

Once the file is open, enter the following:

#!/bin/sh
sleep 30
/usr/local/bin/zfoned
exit 0

Save and exit. This approach makes sure that the
zfoned daemon starts after the desktop
by delaying Zfone activation by 30 seconds. There's a substantial delay in
loading the desktop if
rc.local calls the
zfoned daemon directly:

# nano /etc/rc.local

To prevent this problem, add
these lines above exit
0:

echo "start zfone and zfoned"
sh /etc/init.d/zfonestart.sh

Save and exit.

KDE 3.5.x Setup

Create a new desktop icon by right-clicking the desktop and
selecting Create New > Link to Application. In the New Properties window,
click the General tab and enter zfone in
the text window next to the icon. Click the Applications tab and enter
/usr/local/bin/zfone in the Command
window.

Open the file manager. If you don't have it set to display
hidden files by default, select that option. Open
/home/username/Desktop.
Select the new
zfone.desktop file and
cut it; then open the
/home/username/.kde/Autostart
directory and paste the file. You can now reboot. Zfone should appear in the KDE
System Tray.

NOTE

No instructions are available for KDE 4.x at this time.

Gnome Setup

Choose Menu > Control Center > Personal > Sessions. The
Startup Programs tab should be displayed. If not, select it and choose Add. In
the new window, enter zfone for Name and
/usr/local/bin/zfone for Command. Save
and reboot. Zfone should appear in the Gnome System Tray.

Setting Preferences in the Zfone Client

Right-click Zfone in the System Tray and select Preferences to
open the tab-based interface. On the General tab, select all
except Hear ctx. On the Crypto tab, do
nothing. For Sniff, check all. If you're using Gizmo, that's all you need to do;
otherwise, check the program documentation in whatever VoIP application you're
using, to find out what ports you need to set.